Universal continuous casting apparatus

ABSTRACT

There is disclosed an apparatus for continuously casting metal in various cross sectional shapes, such as blooms, billets, &#39;&#39;&#39;&#39;dog bones&#39;&#39;&#39;&#39; of various proportions, and the like. A plurality of rolls are disposed in tiers along the first portion of the arcuate path of the continuously cast material as it solidifies. Each roll of each tier in said portion is adjustable as to its position by an individual motor. The individual rolls are individually advanced and retracted, either by hand, by any suitable well known type of numerical control, or by means of a pantograph mechanism having a stylus following a template of the desired shape with a position feedback to scan the positions of the individual rolls. In any of the above ways, the rolls of the tiers are positioned to produce in the solidifying steel a shape corresponding to the shape required. A change-over in shape to be produced can be accomplished speedily, thus avoiding a shut-down of several days.

United States Patent 11 1 LaTour 1 Dec. 2, 1975 [75] Inventor: Harry LaTour, Middletown, Ohio [73] Assignee: Armco Steel Corporation,

Middletown, Ohio [22] Filed: May 16, 1974 [21] Appl. No.: 469,815

FOREIGN PATENTS OR APPLICATIONS 1,114,073 5/1968 United Kingdom 164/282 Primary E.\'aminerR. Spencer Annear Attorney, Agent, or Firm-Melville, Strasser, Foster & Hoffman [57] ABSTRACT There is disclosed an apparatus for continuously casting metal in various cross sectional shapes, such as blooms, billets, dog bones" of various proportions, and the like. A plurality of rolls are disposed in tiers along the first portion of the arcuate path of the continuously cast material as it solidifies. Each roll of each tier in said portion is adjustable as to its position by an individual motor. The individual rolls are individually advanced and retracted, either by hand, by any suitable well known type of numerical control, or by means of a pantograph mechanism having a stylus following a template of the desired shape with a position feedback to scan the positions of the individual rolls. In any of the above ways, the rolls of the tiers are positioned to produce in the solidifying steel a shape corresponding to the shape required. A changeover in shape to be produced can be accomplished speedily, thus avoiding a shut-down of several days.

11 Claims, 11 Drawing Figures U.s. Patent Dec.2, 1975 sheet 1 on 3,923,093

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Sheet3 0f3 3,923,093

US. Patent Dec. 2, 1975 UNIVERSAL CONTINUOUS CASTING APPARATUS BRIEF SUMMARY OF THE INVENTION The continuous casting of metals, particularly steels, is now coming into rather general use. Before the .advent of continuous casting, the practice was to pour the molten steel into an ingot mold. After some cooling, the ingot was stripped from the mold and passed to a blooming mill in which the bloom was rolled into a billet which was then further processed in various ways.

In continuous casting, the steel is continuously poured into an apparatus which usually has a water cooled mold at its entrance end, in which the steel starts to solidify. The partially solidified steel issuing from the mold then generally follows an arcuate path defined by a series of rollers (generally referred to as a roller apron) which changes the direction of movement of the steel from the vertical to the horizontal. By the time the steel emerges in a horizontal direction, it has mostly solidified and may then be cut into billets and the like.

It has also been possible to continuously cast a socalled dog bone" configuration which is useful for the production of parallel flanged beams, such as H-beams and I-beams. Thus, the conventional mold with a rectangular bore is replaced with a mold having a dog bone configuration, and in the roller apron section (which defines the above mentioned arcuate path) the conventional top, bottom and edge rolls are replaced with rolls to act on the top and bottom of the web portion, the top and bottoms of both flanges, and the faces of the flanges. To change the casting machine over from the production of flat billets to the production of dog bones requires a shut-down of several days, which of course is a great disadvantage in terms of costs. The alternative is to provide a casting machine for each shape to be produced, but this requires heavy capital investment.

According to the present invention, the tiers of rollers in about the first one-third of the roller apron are made individually adjustable so that they may be positioned by a hydraulic motor in accordance with the shape which it is desired to produce. The positioning of the individual rollers may be accomplished in known ways by numerical control. Alternatively, a template of the shape to be produced by these rollers may be used. A stylus may follow the contour of the template and the signal from the template-stylus to the individual hydraulic motors may be hydraulic, with a conventional position feedback. Thus, by the use of an appropriate set of templates or by the use of suitable tapes or punch cards, a changeover in the shape to be produced by the continuous casting machine may be accomplished as fast as the design speed of the hydraulic motors permits.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS FIG. 1 is a somewhat diagrammatic view of the roller apron section of a continuous casting machine.

FIG. 2 is an enlarged fragmentary diagrammatic elevational view of the first part of the roller apron showing one arrangement for movement of the rollers.

FIG. 3 is a view similar to FIG. 2 showing another arrangement for movement of the rollers.

FIG. 4 is a cross sectional view through one of the hydraulic bearing rollers taken on the line 44 of FIG. 6.

FIG. 5 is an elevational view as seen from the right of FIG. 4.

FIG. 6 is a cross sectional view taken on the line 66 of FIG. 4.

FIG. 7 is a fragmentary diagrammatic view similar to FIGS. 2 or 3 showing the drive for adjusting the position of the rollers.

FIG. 8 is a plan view showing a typical arrangement of the rollers in one tier.

FIG. 9 is a diagram showing a pantograph and template arrangement for positioning the rollers to produce a dog boneshape.

FIG. 10 illustrates several cross sections which may be produced according to the invention; and

FIG. 11 is a diagrammatic showing of the use ofa numerical control device instead of the template arrangement of FIG. 9.

DETAILED DESCRIPTION Referring first to FIG. 1, there is shown in cross section more or less diagrammatically, a continuous casting machine of conventional design. A tundish is indicated at 10 from which molten metal is poured into a water cooled mold 11. While a straight mold has been illustrated, a curved mold may be used without departing from the spirit of the invention. As the molten steel issues from the mold, the skin has already hardened and the steel then passes into the roller apron indicated generally at 12. The roller apron is arcuate and causes the steel to change direction from vertical to horizontal as it passes through the roller apron. As can be seen in the drawing, the molten part of the metal is indicated at 13 while the solidified skin is indicated at 14 and it can be seen that the metal solidifies progressively as it passes through the roller apron 12. The metal then issues at the lower end of the roller apron and passes through subsequent processing apparatus indicated generally at 15.

The present invention relates to that portion of the.

roller apron above the line AA and this constitutes approximately the first one-third of the roller apron.

According to the present invention, the rollers which contact the solidifying metal in the first one-third of the roller apron are individually adjustable toward and away from the solidifying metal. FIGS. 2 and 3 illustrate diagrammatically two different lines of adjustment. In FIG. 2 the individual rollers 16 are adjustable radially with respect to the roller apron and the path of the solidifying metal 14. According to FIG. 2, the adjustment is horizontal.

Each of the rollers 16 is preferably a hydraulic bearing roller, as best seen in FIGS. 4, 5, and 6. Hydraulic bearing rollers are known and do not constitute a part of the present invention. Generally speaking, however, the roller 16 is in the form of an annulus which rotates about a cylindrical member 17 with clearance 18. Water under high pressure is introduced at 19 and enters the bore 20 from whence it passes through the opening 21 into the annular space 18. The member 17 is non-rotatably mounted between side plates 22, and these may be provided with passages 22a to furnish the water spray 22b. These sprays are diagrammatically shown in FIGS. 2 and 3.

The mounting 22 of each hydraulic roller bearing 16 has secured to it a lead screw 23 which is in engagement with a nut 24 having a spur gear 25 secured thereto or integral therewith. The spur gear 25 is driven by a pinion 26 secured to the shaft of a hydraulic motor 27. Thus, when the hydraulic motor 27 rotates in one direction or the other, a drive is transmitted from the pinion 26 to the spur gear 25 and of course to the worm nut 24, whereby the screw 23 is caused to move to the left or right, as seen in FIG. 7, thus retracting or advancing the respective hydraulic bearing rollers 16. It will be understood that the hydraulic motors are shown by way of illustration, and that electric or other motors may be used as desired.

In a conventional roller apron (and this is true in the lower portion of the roller apron 12 below the line AA) there are rollers to contact each face of the solidifying metal 14 and other rollers to contact each edge, there being thus a total of four rollers.

According to the present invention, there are provided a plurality of rollers to contact each face. Thus, as best seen in FIG. 8, there are the hydraulic bearing rollers 30, 31, 32, 33, and 34. A series of similar rollers 30, 31', 32', 33 and 34 contact the opposite face of the solidifying metal. In the particular configuration of FIG. 8, it is desired to produce a dog bone configuration in the metal 14. For this purpose the hydraulic bearing rollers 30, 30, 34 and 34' are retracted while the hydraulic roller bearing 31, 31 32, 32', 33, 33 are advanced. It will of course be understood that the conventional rectangular bore mold 11 (FIG. 1) is for this purpose replaced with a mold having a dog bone configuration. The metal as it issues from the dog bone mold has a basically dog bone configuration and has begun to solidify and the rollers 30 to 34, 30 to 34', maintain the solidifying skin until the metal 14 has solidified sufficiently by the time it reaches the line AA (FIG. 1) so that thereafter the metal can be supported by conventional rollers.

It will be clear from what has been said that the configuration to be produced by the continuous casting machine can readily be changed as desired. It is only necessary to substitute a mold 11 having the desired bore configuration and then to adjust the individual rollers 30 to 34, 30' to 34, to the desired configuration. Such a changeover of the positions of the hydraulic bearing rollers may of course be achieved manually by individually actuating the various hydraulic motors 27. As will be clear to those skilled in the art, the motors 27 may be actuated by input from such suitable means as punch cards, tapes, teletype, cathode ray, thumb wheel switch or from graphical means wherein the shape is called from a computer memory, and relayed to the casting machine controls. The means for automatically providing a signal to the motors to position them for the desired shape may include a programmable digital processor, a hardwire digital processor or hardwire analog processor. The term hardwire refers to integrated circuits which cannot be altered unless they are rewired, and are thus not programmable. The term digital refers to a computer which operates with numbers expressed directly as digits in a decimal, binary or other system. The term analog refers to a computer which operates with numbers represented by directly measurable quantities such'as voltages, resistances or rotations. The specific numerical control apparatus and circuitry does not form a part of the invention and will not be described therefore since it is well known in the art.

In FIG. 9 there is shown diagrammatically a way in which adjustment of the several rolls may be accomplished by means of a pantograph mechanism. In the view of FIG. 9, there are shown not only the rolls to 34 and 30' to 34 but also the end rolls and 35. A template of the shape desired to be produced is indicated at and pantograph mechanisms having styluses 41 are also shown. The styluses trace the configuration of the template 40 and by means of the conventional hydraulic feedback position system, the positions of the various rolls 30 to 35 and 30' to 35 are determined. In this way all of the rolls in approximately the first one-third of the roller apron may be positioned as fast as the design speed of the hydraulic motors permits in a single operation. A template may be used which is rectangular and of any desired length and width for the production of billets and a template such as the template 40 may be used to provide a dog bone shape and of course different templates 40 may be provided for variations in the specific dog bone dimensions.

Whereas heretofore a changeover in a casting machine from the production of billets to the production of dog bones" has necessitated a shut-down of several days or alternatively the provision of several casting machines, the present invention makes it possible to make the changeover on a single machine in a very short period of time.

FIG. 10 shows, by way of example, a billet, a bloom and a dog bone of a different configuration. Any of these shapes, as well as others, may be produced by use of an appropriate template 40, or by the use of appropriate punch cards or tapes in the numerical control device indicated diagrammatically at 42 in FIG. 11.

It will be understood that numerous modifications may be made without departing from the spirit of the invention and that therefore no limitations not expressly set forth in the claims are intended and no such limitations should be implied.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In a continuous metal casting machine having a mold through which molten metal may be poured, said mold communicating with a roller apron through which the solidifying metal passes, a roller arrangement for the rolls of about the first one-third of said roller apron comprising:

a. a plurality of cylindrical rollers arranged in tiers, the rollers of each tier being adapted to contact each side and each edge of the metal as it issues from said mold in partially solidified form,

b. each of said rollers in each tier being individually adjustable inwardly and outwardly with respect to the path of said metal whereby to determine the cross sectional configuration of the solidifying metal.

2. Apparatus according to claim 1, wherein the direction of'adjustment of each of said rollers is horizontal.

3. Apparatus according to claim 1, wherein the direction of adjustment of each of said rollers is radial of the arc of said roller apron.

4. Apparatus according to claim 1, wherein each of said rollers is a hydraulic bearing roller.

5. Apparatus according to claim 1, wherein individual hydraulic motors are the prime movers for the adjustment of said rollers.

6. Apparatus according to claim 1, wherein each said tier of rollers includes one roller for each edge and five rollers for each side of the solidifying metal.

7. Apparatus according to claim 1, wherein means are provided to adjust all of said rollers in each of said tiers concurrently to determine the cross sectional configuration of the cast metal as it solidifies in passing through the first portion of said roller apron.

8. Apparatus according to claim 1, wherein a template is provided for each different cross sectional shape it is desired to produce, and a pantograph having a stylus is arranged to trace the outline of said template,

tional shape by signals from a hardwired analog device. 

1. In a continuous metal casting machine having a mold through which molten metal may be poured, said mold communicating with a roller apron through which the solidifying metal passes, a roller arrangement for the rolls of about the first one-third of said roller apron comprising: a. a plurality of cylindrical rollers arranged in tiers, the rollers of each tier being adapted to contact each side and each edge of the metal as it issues from said mold in partially solidified form, b. each of said rollers in each tier being individually adjustable inwardly and outwardly with respect to the path of said metal whereby to determine the cross sectional configuration of the solidifying metal.
 2. Apparatus according to claim 1, wherein the direction of adjustment of each of said rollers is horizontal.
 3. Apparatus according to claim 1, wherein the direction of adjustment of each of said rollers is radial of the arc of said roller apron.
 4. Apparatus according to claim 1, wherein each of said rollers is a hydraulic bearing roller.
 5. Apparatus according to claim 1, wherein individual hydraulic motors are the prime movers for the adjustment of said rollers.
 6. Apparatus according to claim 1, wherein each said tier of rollers includes one roller for each edge and five rollers for each side of the solidifying metal.
 7. Apparatus according to claim 1, wherein means are provided to adjust all of said rollers in each of said tiers concurrently to determine the cross sectional configuration of the cast metal as it solidifies in passing through the first portion of said roller apron.
 8. Apparatus according to claim 1, wherein a template is provided for each different cross sectional shape it is desired to produce, and a pantograph having a stylus is arranged to trace the outline of said template, said stylus being connected to said several hydraulic motors to cause them to operate and position said several rollers in conformity with the configuration of said template.
 9. Apparatus according to claim 1, wherein inputs to said rollers are provided for each desired cross sectional shape by signals from a programmable device.
 10. Apparatus according to claim 1, wherEin inputs to said rollers are provided for each desired cross sectional shape by signals from a hardwired digital device.
 11. Apparatus according to claim 1, wherein inputs to said rollers are provided for each desired cross sectional shape by signals from a hardwired analog device. 